1. Field of the Invention
The present invention relates to a display apparatus. More particularly, the present invention relates to a projection apparatus.
2. Description of Related Art
With development of projection display technique, the projection apparatus has been widely applied to people's daily life. Since the projection apparatus may project an image frame with a size thereof larger than a size of a general large-size television, while a cost thereof is lower than that of the general large-size television, it has an irreplaceable place in the display domain. For example, academic units or companies generally apply the projection apparatus for teaching or briefing since the projected large-size image frames are suitable for being simultaneously viewed and discussed by a plurality of people. Moreover, the projection apparatus also become main equipments for home theaters.
Generally, the projection apparatus is disposed on a desktop or is hung to a ceiling. The projection apparatus disposed on the desktop is hard to project an image frame onto the desktop. If the image frame is constrainedly projected onto the desktop, the image frame has a shape of trapezium due to an oblique projection. Objects in the trapezium-shape image frame are deflective and are not suitable for viewing. Moreover, though the projection apparatus hung to the ceiling may project the image frame onto the desktop, time and cost are spent for assembling the projection apparatus to the ceiling. In addition, once the position of the desktop is changed, reassembling of the projection apparatus is required, so as to lead to more consumption of human labor, time and assembling cost. Moreover, the projection apparatus assembled to the ceiling may not be carried to other places for utilization, such that applicability of the projection apparatus is decreased.